Catalytic Effect of Iron and Titanium on the Microstructure and Properties of Biopitch Anodes

The influence of catalyst on the physical properties and CO₂ reactivity of carbon anodes after baking has been investigated in this paper. Raman spectra and X-ray diffraction patterns show that there is more well-ordered structure in carbon anodes with iron and titanium additives. The metal additives promote the crystalline size of graphite and graphitization extent. The appearance of the interaction between various pitch and coke surface is revealed by the optical microscopy. Gasification induces the anodes disordering to some extent. A detailed investigation indicates that there is a close relationship between the microstructure and anode properties. Owing to the improvement of graphitization extent, the properties of biopitch anodes with metal additives are better than that of conventional coal-tar-pitch samples, which can mitigate the adverse impact of its low coking value and amorphous structure on the density of the anodes. The catalytic graphitization mechanism is proposed for the transition of amorphous carbon to graphite structure at a lower temperature. The results indicate that the biopitch anodes with iron and titanium as catalysts are promising for potential application. This study proposes a green method for designing a high coking value carbon anode with biopitch as a binder by catalytic graphitization.

Graphical Abstract